NASA Media Telecon on Probes' Moon Orbit Insertion

Artist concept of GRAIL mission. Grail will fly twin spacecraft in tandem orbits around the moon to measure its gravity field in unprecedented detail. Image credit: NASA/JPL › Larger image

PASADENA, Calif. -- NASA will hold a media teleconference at 11 a.m. PST (2 p.m. EST) on Wednesday, Dec. 28, to preview twin spacecraft being placed in orbit around the moon on New Year's Eve and New Year's Day.

NASA's twin lunar Gravity Recovery and Interior Laboratory (GRAIL) probes were launched from Cape Canaveral Air Force Station on Sept. 10, 2011. GRAIL-A is scheduled to arrive in lunar orbit beginning at 1:21 p.m. PST (4:21 p.m. EST) on Saturday, Dec. 31, and GRAIL-B on Sunday, Jan. 1, beginning at 2:05 p.m. PST (5:05 p.m. EST). After confirmation they are in orbit and operating nominally, the two solar-powered spacecraft will fly in tandem orbits to answer longstanding questions about the moon and give scientists a better understanding of how Earth and other rocky planets in the solar system formed.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the GRAIL mission. The Massachusetts Institute of Technology, Cambridge, is home to the mission's principal investigator, Maria Zuber. The GRAIL mission is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.